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Lowly ants play important natural role

A sawdust pile at the base of this pine tree betrays the presence of active boring insects. In this case it's carpenter ants. Keith Corliss

Motel maids are not usually considered integral to the success or failure of an economy. Likewise perhaps, the garbage worker, the septic tank emptier, and the busboy could be similarly lumped. Yet without the service these and other somewhat undesirable jobs provide, our entire system begins to strain and eventually break. In essence, then, they are a vitally important piece of this humming, throbbing, pulsing system of ours known as free market capitalism.

A crude parallel can be drawn between the workers in the above paragraph and the lot of the decomposers, those little thought of, but vital engines which keep us from being buried in a never ending accumulation of dead stuff. From carrion-eating vultures to dung beetles to the tiniest single-celled bacterium, comes the yeoman's work of breaking down carbon-based material into ever smaller pieces. Given enough time, the result of their collective work is, well, soil. Or at least a vital component of soil--organic compost, the stuff in which the cycle starts all over again with new plants, new plant eaters, new eaters of plant eaters, etc. Call it the circle of life, call it the carbon cycle, call it what you will, but try and imagine how quickly this eons-old system would crash without all those little underappreciated critters breaking it all down.

This is the thought which came to mind last week as my wife and I were hiking along a trail in the mountains of southwestern Montana and came upon a sizable pile of sawdust or frass (def.: excrement or other refuse left by insects and insect larvae) at the base of a moderately sized pine tree. It was obvious there was wood boring taking place. Lots of it.

Getting down on our hands and knees and looking carefully at the hub of activity, we noticed numerous large black ants taking turns appearing at the entrance to various wood tunnels, dumping their burden of tiny wood pieces, then retreating back into the darkness, presumably to gather another load. They were carpenter ants.

Carpenter ants are found nearly worldwide, all falling within the genus Camponotus. There are over 1,000 species in the genus with numerous representatives here in North America. Unfortunately, they can be a large pest problem in homes in ways not unlike termites. That is, ants drill galleries into wood which can cause structural damage. Millions of dollars are spent by homeowners annually fending off the work of carpenter ants.

In a way, carpenter ants are the insect counterparts of woodpeckers. That is, instead of healthy wood or trees, they usually inhabit only moist or decaying wood. Over time the colony can expand to include healthy wood but for homeowners, the initial presence of carpenter ants should be a signal there is something wrong with the home's circulation or the integrity of the wood itself.

Unlike termites, carpenter ants do not eat wood. Protein and sugars make up their diet. In the wild this means eating other insects either living or dead. The wood-boring habit is nothing more than the critters creating and maintaining a place to live and nest.

Carpenter ants, like most other ant species, are colonial. Meaning they each exist for the betterment of the group ahead of any concern for individuals or themselves, in a sort of Marxist utopia. Work is divided along caste lines in ways similar to honey bees. There is a queen, there are classes of workers, and there are reproductive individuals, each playing a tiny but vital role in the destiny of the colony.

A healthy forest does not look like the city park where you walk your dog. That is a landscape highly modified to fit our human idea of safe urbanized nature. Instead, a wild robust forest is a somewhat chaotic place, at least to our eyes. It's full of a dizzying variety of forbs, grasses, and trees of all makes and models in all stages of life. And yes, there are dead trees about, being slowly, inexorably, and relentlessly reduced to organic dust. Indeed, the herculean job of recycling the once-mighty trees into usable earthy substances is left to some of the smallest organisms, including carpenter ants.